Assignment cancelling circuit



Aug. 23, 1955 o. M. SALATI 2,716,206

ASSIGNMENT CANCELLING CIRCUIT Filed April 16, 1952 INVENTOR.

OCTAVIO M. SALATI Affomey United States Patent ASSIGNMENT CANCELLINGCIRCUIT Application April 16, 1952, Serial No. 282,547

1 Claim. (Cl. 317-137) This invention relates to a circuit arrangementinclud ing a plurality of magnetic relays and having means associatedtherewith for energizing one of said relays and simultaneouslyde-energizing the remainder of said relays.

This invention will be more clearly understood by reference to thedrawing wherein the figure shown represents a preferred embodimentthereof. The circuit arrangcment shown has four magnetic relays a, b, cand d. Like parts throughout the drawing and specification will bedesignated by like numerals plus the suffix a, b, c or d to identify thepart with its associated relay. Each relay has a set ofbreak-before-maltc leaves consisting of a pair of stationary leaves and12 and a main leaf 14, and a set of make-before-break leaves consistingof a stationary leaf 20, a main leaf 22, and a secondary leaf 24. Alsoassociated with each of said relays is a grounded armature 30 having anassociated resistance 32. The break-before-make leaves are connected ina series arrangement while the make-beforebreak leaves are connected ina parallel arrangement. The output from each armature is generally takenbetween the terminals 34 and ground 36 of the respective relays. Agrounded power supply 40 is provided to hold the relays a, b, c or d inposition once they are actuated.

The circuit arrangement shown may further be considered to haveassociated with each relay a locking circuit and an actuating circuit.

The actuating circuit of each relay may be seen to consist of itsassociate grounded armature 30 and leaves 7.0, and 24 of its associatedset of make-before-break leaves. Each actuating circuit is energizedthrough 1111 external signal source 50. The locking circuit of eachrelay may be considered to include its associated grounded armature 30the secondary and main leaves 24 and 22 of its associated set ofmake-before-break leaves, the main leaf 14 and the stationary leaf 12 ofits associated set of break-before-make leaves, the main leaves 14 andthe stationary leaves 10 of the remaining sets of break-beforemakeleaves, and the common grounded power supply 40.

The operation of the circuit will be explained in particular withreference to relays a and b. The original state of operation will beassumed to be indicated by the solid line representation. That is, relayb actuated, all other relays unactuated. Assuming now that relay :1 isactuated by a pulse through terminal 50a, the relays a and b will takethe positions shown by the dashed lines. First the actuating circuit ofrelay a will be actuated through armatures 30a, leaves a and 24a, and;the signal source supplied through terminal 50a. This will cause themain leaves 14a and 22a (since they are physically connected as byinsulated bar 60) of relay a to be pulled down and held in the positionshown by the dashed lines, thereby breaking the actuating circuit ofrelay a since contact between secondary leaf 20a and main leaf 24a mayno longer exist, and simultaneously unlocking relay b since themomentary opening be 2,716,206 Patented Aug. 23, 1955 tween leaves Illaand 14a (until leaf 14a contacts leaf 12a) opens the locking circuit ofrelay b thus allowing relay b to take the position shown by the dashedlines.

Further analysis of the circuit will disclose that only one relay of theabove circuit arrangement may be locked at any one time, and by anexplanation similar to that given above with reference to relays a andenergization of any actuating circuit associated with a relay will causethat relay to be locked in and any previously locked relay to beunlocked. It may also be seen that any number of relays may be arrangedin the manner disclosed, the only provision being that each relay addedhave associated therewith an armature, and a set of make-before-breakand break-before-make leaves similar to those associated with relays a,b, c and d herein described. It should be noted that the main leaves 14aand 22a of initial relay a" are electrically connected as well asphysically coupled, while the main leaves of each of the remainingrelays are not electrically connected but are physically coupled so thatthey must move together.

A particular advantage of the circuit arrangement herein dscribed isthat, as more relays are added, the number of leaves associated witheach relay remains the same; thus additional relays may be added at anytime without disturbing any of the other relays in the arrangement otherthan the last relay to which the new relay is to be connected. Even thislatter disturbance, if any, is nil.

While there have been described what at present are considered to bepreferred embodiments of the invention, it will be understood by thoseskilled in the art that various changes and modifications may be madeherein without departing from the invention and it is therefore aimed inthe appended claim to cover all such modifications as fall within thespirit and scope of the invention.

What is claimed is:

A circuit arrangement comprising a plurality of magnetic relays eachhaving a two terminal coil, and each having a set of break-before-makeleaves comprising first and second fixed leaves and a first movable mainleaf between said two fixed leaves, and a set of makebeforebreak leavescomprising a second movable main leaf, a movable secondary leaf and athird fixed leaf between said second movable main leaf and saidsecondary leaf, said first fixed leaf being in contact with said firstmain leaf and said third fixed leaf being in contact with said secondaryleaf when said coil is not energized, and said second fixed leaf beingin contact with said first main leaf and said secondary leaf being incontact with said second main leaf when said coil is energized, thefirst and second fixed leaves of each relay being connected together andalso connected to the first main leaf of the next succeeding relay ofsaid plurality of relays, the second main leaf of the first of saidrelays being connected to the first main leaf of said first relay and tothe second main leaf of each succeeding relay of said plurality ofrelays, the secondary leaf of each relay being connected to one terminalof its coil, the other terminal of each coil being grounded, the thirdfixed leaf of each relay being connected to a separate source of relayenergizing potential respectively, and the first and second fixed leavesof the last relay of said plurality of relays being connected to asource of holding voltage.

References Cited in the file of this patent UNITED STATES PATENTS2,250,923 Weld July 29, 1941 2,322,563 Bruno June 22, 1943 2,413,741Young Jan. 7, 1947 2,593,578 Liberg Apr. 22, 1952

